Corrosion of steel pipes can degrade the structural integrity of the pipeline system. In some pipeline systems, the metallic pipe is insulated with a urethane foam covering and protected by an outer metallic shield. In other pipeline systems, the metallic pipe is buried. For insulated, shielded pipes, visual inspection is impossible without physically removing the insulation and outer shield. For buried pipes, visual inspection is also impossible without excavating the pipe.
Current methods of testing pipe without removing the insulation and outer shield or excavation include acoustic wave propagation through the metal and x-ray radiography. However, acoustic wave propagation and x-ray radiography are only applicable to a single point location or over a short distance.
The need thus exists for improved systems and methods for testing for anomalies on a length of pipe without excavation or removing the shielding and insulation.